The invention relates to an upsetting press for reducing the width of rolling stock, and particularly to a press for reducing the slab width in hot-rolled wide strip roughing mills with tool carriers, which are disposed on either side of the slab edge, accommodate pressing tools and can be moved in the direction of reducing the slab with the help of a steering system, which is operated by at least one crank gear.
The German Offenlegungsschrift 25 31 591 discloses an upsetting press for reducing the width and thickness of slabs of different width, which are supplied by a continuous plant. The slab is processed repeatedly in the upsetting press with pressure tools that are moved against one another. The pressure tool is able to follow the advance of the slab freely and the tools are operated so that they carry out a relatively slow working sequence and a relatively rapid idle motion. The upsetting press has a pair of edge processing tools which act vertically upon the edges of the slab, as well as means for moving the tools back and forth rapidly. The tools are held in a tool support, which is moved by a crank gear, and are pivoted at the tool carrier with pivot pins. The upsetting forces, required for reducing the width of the slab, must be transferred from the pivot pin support to the tool carrier and onto the pressure tool. The resulting high frictional forces consequently reduce the output of the press and the high attrition of the pivot pins increases the maintenance costs and decreases the availability not only of the upsetting press, but also of the whole rolling mill, into which the press is tied.
In the flying upsetting press of German patent P 39 17 398.4, pressing tools, which are accommodated in tool supports, are disposed in hot-rolled wide strip roughing mill on both sides of the slab edge in order to reduce the width of slabs. To form a reduction drive, each pressing tool is moved with the associated tool support, with the help of a steering system operated by a crank gear, in the direction of a width reduction of the slab, the crank gear being disposed in a crankcase. The crank gear consists of two driven eccentric shafts, and a connecting rod is mounted on each eccentric shaft. The head of the connecting rod is in operative connection with the tool support for the transfer of upsetting forces. A feed driving mechanism, which acts essentially in the direction in which the slab is fed, engages the tool support. By means of these measures, the course of the motion of the pressing tools can be controlled separately for reducing pressing and for advancing the pressing tools. In the event that the feed driving mechanism is constructed as a hydraulic cylinder, the positioning motion of the hydraulic cylinder can be controlled in a particularly advantageous manner in the form of a path-time function so that, for an advance of any magnitude, the synchronization between the motion of the pressing tool and the motion of the slab that is to be pressed laterally is ensured. During the pressing process, the connecting rod is moved angularly only through a fraction of a degree by the appropriate controlling mechanism of the feed cylinder and through only a few degrees during the idling phase, so that an effective build-up of lubricant can be brought about in the bearing of the head of the connecting rod.